Radio frequency (RF) communications devices are used in a wide variety of applications such as cellular or mobile telephones, cordless telephones, personal digital assistants (PDAs), computers, radios and other devices that transmit or receive RF signals. As communications devices become increasingly integrated and more portable, the efficiency in transmitting an output signal or receiving an input signal tends to increase in importance. Accordingly, it would be desirable to maximize the signal selectivity and minimize the signal-to-noise ratio of a transmitted or received signal in a communications device.